/*++

Copyright (c) Microsoft Corporation. All rights reserved.

You may only use this code if you agree to the terms of the Windows Research Kernel Source Code License agreement (see License.txt).
If you do not agree to the terms, do not use the code.


Module:

    stdarg.h

Abstract:

    Defines ANSI-style macros for variable argument functions

    This file defines ANSI-style macros for accessing arguments
    of functions which take a variable number of arguments.
    [ANSI]
    [Public]

--*/

#if     _MSC_VER > 1000
#pragma once
#endif

#ifndef _INC_STDARG
#define _INC_STDARG

#ifdef  _MSC_VER
/*
 * Currently, all MS C compilers for Win32 platforms default to 8 byte
 * alignment.
 */
#pragma pack(push,8)
#endif  /* _MSC_VER */

#ifdef  __cplusplus
extern "C" {
#endif


#if !defined(_W64)
#if !defined(__midl) && (defined(_X86_) || defined(_M_IX86)) && _MSC_VER >= 1300
#define _W64 __w64
#else
#define _W64
#endif
#endif

#ifndef _UINTPTR_T_DEFINED
#ifdef  _WIN64
typedef unsigned __int64    uintptr_t;
#else
typedef _W64 unsigned int   uintptr_t;
#endif
#define _UINTPTR_T_DEFINED
#endif

#ifndef _VA_LIST_DEFINED
typedef char *  va_list;
#define _VA_LIST_DEFINED
#endif

#ifdef  __cplusplus
#define _ADDRESSOF(v)   ( &reinterpret_cast<const char &>(v) )
#else
#define _ADDRESSOF(v)   ( &(v) )
#endif

#if     defined(_M_CEE)

extern void __cdecl __va_start(va_list*, ...);
extern void * __cdecl __va_arg(va_list*, ...);
extern void __cdecl __va_end(va_list*);

#define va_start(ap,v)  ( __va_start(&ap, _ADDRESSOF(v), sizeof(v), \
                                __builtin_alignof(v), _ADDRESSOF(v)) )
#define va_arg(ap,t)    ( *(t *)__va_arg(&ap, sizeof(t), \
                                __builtin_alignof(t), (t *)0) )
#define va_end(ap)      ( __va_end(&ap) )

#elif   defined(_M_IX86)

#define _INTSIZEOF(n)   ( (sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1) )

#define va_start(ap,v)  ( ap = (va_list)_ADDRESSOF(v) + _INTSIZEOF(v) )
#define va_arg(ap,t)    ( *(t *)((ap += _INTSIZEOF(t)) - _INTSIZEOF(t)) )
#define va_end(ap)      ( ap = (va_list)0 )

#elif defined(_M_AMD64)

extern void __cdecl __va_start(va_list *, ...);

#define va_start(ap, x) ( __va_start(&ap, x) )
#define va_arg(ap, t)   \
    ( ( sizeof(t) > sizeof(__int64) || ( sizeof(t) & (sizeof(t) - 1) ) != 0 ) \
        ? **(t **)( ( ap += sizeof(__int64) ) - sizeof(__int64) ) \
        :  *(t  *)( ( ap += sizeof(__int64) ) - sizeof(__int64) ) )
#define va_end(ap)      ( ap = (va_list)0 )

#else

/* A guess at the proper definitions for other platforms */

#define _INTSIZEOF(n)   ( (sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1) )

#define va_start(ap,v)  ( ap = (va_list)_ADDRESSOF(v) + _INTSIZEOF(v) )
#define va_arg(ap,t)    ( *(t *)((ap += _INTSIZEOF(t)) - _INTSIZEOF(t)) )
#define va_end(ap)      ( ap = (va_list)0 )

#endif

#ifdef  __cplusplus
}
#endif

#ifdef  _MSC_VER
#pragma pack(pop)
#endif  /* _MSC_VER */

#endif  /* _INC_STDARG */

